New forms of power generation and storage have introduced a need for ways to interface with them. One interfacing method, such as solar power generation, converts solar power into a more useable form.
A solar panel can include an array of series/parallel-connected solar cells. The voltage produced by the solar panel can be too low to be used directly in an application for supplying electricity to the grid. On the other hand, the voltage can be too high to be fed directly to a battery or array of batteries. In addition, the power output of a solar panel can depend greatly on the lighting conditions. As a result, the output power of a solar panel can fluctuate rapidly.
Therefore, implementation of modular solar energy systems where solar panels or a group of panels are directly connected to a low voltage or a high voltage bus usually specifies the use of a maximum-power-point-tracking (MPPT) converter with a large conversion ratio. The converter converts the voltage produced by the solar panels into another voltage which is more suitable for the application. A conventional way to interface with solar panels is to use a voltage-fed switching converter.
A disadvantage associated with the above arrangement is due to its limited operational range. The application may have to operate under conditions specifying a greater operational range. The solar systems are also known to be sensitive to common mode currents, which can reduce the useful life of the solar cells and cause human safety issues when using conventional converters.